Week 3: The Blood and Body defences: Too Much or Too Little

Question 1

What is polycythemia vera?

Answer 1

An excess of red blood cells in the circulation

Question 2

What is essential thrombocytopenia?

Answer 2

Excess of Platelets

Question 3

What is idiopathic myelofibrosis?

Answer 3

Too few RBC, too many platelets and WBC

Question 4

What is primary polycthemia?

Answer 4

Genetic Problems with RBC - primary familial and congenital polycythaemia due to enhanced responsiveness to EPO. Most commonly due to Mutations in JAK 2

Question 4

What is primary polycthemia?

Answer 4

Genetic Problems with RBC - primary familial and congenital polycythaemia due to enhanced responsiveness to EPO. Most commonly due to Mutations in JAK 2

Question 5

What is secondary polycthaemia?

Answer 5

Due to conditions that promote RBC development.

1) Hypoxia
2) EPO secreting tumors
3) Neonatal Polycythaemia

Question 6

What is relative polycythaemia?

Answer 6

RBCs normal but reduced plasma volume

Question 7

What is JAK 2 gene?

Answer 7

Non receptor tyrosine kinase

Question 8

How does the mutation effect JAK2?

Answer 8

The mutation takes place in the TK like domain which is responsible for the inhibitory role
The mutation, therefore, makes JAK2 constitutively active in the absence of ligand binding

Question 9

What are the features of type 1 (Immediate) Hypersensitivity?

Answer 9

Immune reactant= IgE
Antigen = Soluble antigen
Effector Mechanism = Mast cell activation
Examples of hypersensitivity reaction: allergic rhinitis, asthma, anaphylaxis
Mast cell binds on the Fc component of IgE

Question 10

What are the consequences of type 1 hypersensitivity?

Answer 10

Question 11

What are the features of type 2 hypersensitivity?

Answer 11

Question 12

what are the features of type 3 hs (immune complex disease)?

Answer 12

can effect renal glomerule

Question 13

What are the features of type 4 hs (delayed)?

Answer 13

Question 14

Why is there a delay in type 4 HS?

Answer 14

Takes time for Th1 cells to recognise antigens, release cytokines and and recruit other leukocytes

Question 15

Example of primary immunodeficiency?

Answer 15

Chronic Granulomatous disease

Question 16

Example of secondary immunodeficiency?

Answer 16

HIV/AIDS

Question 17

What is chronic gramatulous disease?

Answer 17

A genetic disorder that affects how phagocytes kill bacteria, fungi and parasites
4 major forms due to mutation in the different proteins that comprise the phagocyte oxidase system
Recessive Sex-linked

Question 18

What is HIV?

Answer 18

A retroviral infection leading to loss of CD4+ T cells

Question 19

What is the impact of secondary immunodeficiency on T cell regulation?

Answer 19

By reducing the number of CD4+ T cells, there is also a reduction in the T cells that it differentiates into such as T reg cells, Th1, Th2 and Th17 and cytokines and TFs.

Question 20

What is autoinflammation?

Answer 20

Prolonged, unwanted Innate Immunity

Question 21

What is autoimmunity?

Answer 21

Loss/ failure of self/ non-self recognition

Question 22

What is tolerance in immuntiy?

Answer 22

When T cells/B cells that can recognise self proteins are removed during development

Question 23

What are 4 ways in which autoimmune diseases can occur by infection?

Answer 23

Molecular Mimicry
Protein Changes, Cryptic Antigens
Super Antigens
Bystander Activation

Question 24

What therapeutic interventions can be used in autoimmune and autoinflammatory disease?

Answer 24

Cytokine therapies
Reducing Lymphocyte Activation - Interefering with signalling pathways, Blocking receptors and active induction of tolerance
Killing the cells causing disease